Calculating Moles

Which of the following would have more mass?

• 1 mole of Li
• 1 mole of Au
• 1 mole of Si
• None, all are equal

How many molecules are there in 31.8 moles of water? (H₂O has a molar mass of 18.0 g/mol)

• 572 g

• 1.91 x 10²⁵ molecules

• 5.28x 10-²⁵ molecules

• 1.77 g

Vitamin C, also known as ascorbic acid, is water soluble and cannot be produced by the human body. Each day, a person's diet should include a source of Vitamin C, such as orange juice. Ascorbic acid has a molecular formula of C₆H₈O₆ and a molar mass of 176 grams per mole.

Determine the number of moles of vitamin C in an orange that contains 0.171 grams of vitamin C.

• 30.1 moles

• 1030 moles

• .000971 moles

• .0001 mole

Calculate the number of moles of chlorine atoms in 55g of copper (II) chloride.

• 0.41 moles

• 0.82 moles

• 1.6 moles

• .20 moles

What is the mass of 0.75 moles of (NH₄)₃PO₄?

• 0.0044 g

• 91 g

• 110 g

• 74 g

Which has more molecules?

• 1 mole H₂O
• 1 mole Al(OH)₃
• 1 mole NaCl
• There are all the same

How many molecules are present in 135 g of Teflon C₂F₄

• 6.13 x 10²³ molecules

• 5.13 x 10²³ molecules

• 8.13 x 10 ²³ molecules

• 9.13 x 10²³ molecules

Which of the following would have the highest number of moles?

• 4g CO₂
• 15g H₂O
• 22g NaCl
• 100g AgCl

Calculate the % composition by mass of oxygen present in H₂SO₄.

• 16.3%
• 65.25%
• 32.6%
• 57.14%

What is the molar mass of calcium hydroxide, Ca(OH)₂?

• 74.1 g/mole

• 57.1 g/mole

• 58.1 g/mole

• 57.1 u